Train-control system



April 23, 19 E. J. BLAKE TRAIN CONTROL SYSTEM Original Filed Augfll 1915 2.Sheets-Sheet INVENTOR. 5 {La (W 34%. BY Q W S ATTORNEYS.

SELECTIVE 3614p April 23, E. J B KE 1,710,495

TRAIN CONTROL SYSTEM Original Filed Aug. 11, 1915 2 Sheet -sh t 2 FE5-2n I 3 J6 (J 56 /..r 1 am ATTORNEYS.

Patented Apr. 23, 1929.

ELI J. BLAKE, or WESTFIELD,

NEW JERSEY, assrenoa, BY mar. ASSIGNMENTS, TO

tmxon'swrron & SIGNAL COMPANY, or SWISSVALE, IPENNSYLVANIA', A CORPORA- TION or PENNSYLVANIA.

TRAIN-correct SYSTEM,

Original application filed August 11, 1915, Serial No. 4 5,078. Divided and this application filed Decemher 5, 1916. Serial No. 135,120.

My invention relates particularly to systerns for controlling the operation of trains by a. method which in its general nature is electrical.

In constructing train control systems where automatic stopping devices are used it is necessary to locate the actuating devices for the-same at such a point as to bring the train to rest before reaching'the entrance of an-occupied block. In the case where the actuating devices are located at a certain definite point for all trains, it is necessary for them to be located'to the rear of the entrance to the braking distance for the fastest train. Furthermore, it has been found necessary previously to locate the stop signal for the engine m'anin the rear of theactuating devices, as it is not desired to remove the responsibility from the engine man to devices of the train stop when the signal to bring the same to .a indicates that the train should be stopped. The minimum headway between the trains .upon a given track is thus very much increased owing to the presence of the signal and actuating devices a considerable distance in the rear of the entrance to each of the blocks and the increase in the minimum headway is the dis-' tance between the stop signal and the entrance to the block. The amount of traffic that can be carried by track in such. a system is therefore correspondingly reduced.

One object of my invention is to provide a train control system which will not interfere with the control of the train by the engineer provided he is governed by the signals, and which will not therefore relieve the engineer of the responsibility of following the Signals in the operation of the train; nor will it require any increase of minimum headway over that which is required with non-:mtomatic control; but which, in the event of the engineers disregarding a stop signal will automatically bring the train to rest near the point indicated by the stop signal, irrespective of the speed at which the train is traveling. Another object of mv invention is to provide means for stopping the train automatically if predetermined speeds are exceeded over particular parts or the whole of the track. Another object is to provide Signals on the train for 'tion is a operate the controlling depend on .the guidance-of the engineer, which signals may be used in addition to, or in place of, fixed signals along the way as ordmarily employed heretofore.

In my priorapplication filed August 11,

1915, Serial #45978, of which this applicadivision, I have disclosed one means that will automatically intervene to bring the train to rest only in the event of the engineers failing to keep the train under such control as will permit of bringing it to rest at the point where safety requires it to come to rest, or failing to reduce the speed of the train to a safe value where such reduction is required, but it is obvious that the present invention is applicable to the control of any other form of train control or cab signal system as desired.

Furthermore, my system is such that Safety is indicated only when all of the devices and circuits controlling the safety indlcation are intact. The parts are, in other words, predisposed to the indication of d'angcr and return automatically to such indication in case the power supply or any other part of the system fails. This is a distinct advantage over prior systems'differently arranged, especially systems which indications of safety received only at particular locations along the track.

In my system safety is indicated continu'- ously by current which flows over the entire block and a fraction of a block in advance of the train.

While my invention is capable of embodiment in many different forms, for the purpose of illustration I have shown only certain forms thereof in the accompanying drawings, in which I Figure 1 is a diagrammatic plan view of the track and the wheels of the car showing an arrangement of the devices on the car for controlling the car from the track;

Figures 2, 3 and 4 are diagraimnatic rcprcsentations of circuits energizing the tracks in different ways in accordance with my invention.

Figure 5 is. a side view of one form of transformer that may be employed inconjunction with the vehicle axle.

\Vhen the blocks are clear and free from danger my system is arranged in such a manner as to indicate this fact to the engine man, and also in such a manner as to close a valve 1 so as to prevent actuation of the brakes. This is accomplished in' the fol- .1, that is to say, by passing along one rail 2, through the wheels and axles and then returning by the other rail 3. Transformers 4 are provided consisting of cores 5 surrounding the axles at the front of the car and coils 6, the coils 6 on a. particular truck being connected together by a wire 7, and being connected together also by a wire 8 which wires are in circuit with a coil 9 of an electromagnet. W'hile I have shown transformers surrounding the first two axles of the train, they may be applied to any number of axles in the train. The use of more than one transformer lessens the possibility of interruption of the circuit due to imperfect contact between the wheels and rails. It will be understood that the alternating current-passing along the rail 2 will divide, part passing through the front axles,

, which are surrounded by the transformer cores, and part continuing along the rail to axles in the rear. The power delivered to the transformers including the drop in the axles on which they are located will only be a very small fraction of the power delivered to the rails as it will be merely the product of the portion of the current that passes through the transformers by a potential equal to the drop in potential in the branch circuit including rails and axles in the rear of the transformers. The electromagnct comprising the coil 9 is arranged so as to decrease the pressure exerted by an armature 10 which is pressed downwardly by a s ring 11 against a pile of carbon discs 12. 'lhis pile of carbon discs 12 is located in a circuit 13 including a battery 14, so that the undulations of the alternating current in the wire 8, by causing variations in the pressure on the pile of carbon discs 12 and thereby causing variations in the resistance of the pile, produce corresponding undulations of magnified intensity in the current flowing through the circuit 13. If desired these undulations can be still further intensified by providing a coil 15 in front ofthe armature 10 which coil is shunted across the carbon pile 12, so that each increase in the resist.- ance of the carbon pile will cause more current to How through the coil 15, tending to still further decrease the pressure upon the carbon discs and increase their resistance. The same process can be repeated any number of times, producing at each stop an undulating current of increased intensity, so that the feeble current received over the circuit 8 can be amplified to any desired extent. For example I have shown another magnet coil 16 in series with the carbon pile 12 which acts upon an armature 17 in opposition to aspring 18 to vary the pressure.

intensity.

In series with the carbon pile 19 I connect a winding 20 of a-relay having a contact finger 21 in a circuit 22 including the bat' tery 14 which is responsive only to periodic currents, and which may be made responsive only to periodic currents of a particular frequency or range of frequencies. Through the contact finger 21 of this relay, and through a wire 23, current passes from the battery 14 to a lamp 24 returning to the battery 14 through a wire 25. A branch circuit in multiple with the lamp 24 and including a magnet coil 26 controlling a. lever 27 on the valve 1 passes through wires 28 and 29. Thus the lamp 24 will be lit and the valve 1 will be held closed if a suitable alternating current is passing through the axles embraced by the transformer cores 5 and not otherwise. The lamp 24 serves as a signal to the engineer, indicating when 'lit that the track ahead is clear to the end of the next block in advance. The valve 1 serves, when the track is clear, to cut off the connection between the air brake system and any desirable form of control mechanism such as disclosed in my prior application, which would otherwise cause the train to stop automatically.

in one form of my system, I rovide not only a source for supplying to t 1e rails the alternating current which I have described, indicated diagrammatically in Figs. 2, 3 and 4 by the supply wires 30 and 31, this current being of a frequency adapted to operate the relay 20, shown in Fig. l, but I also supply an alternating current of a different frequency, to which the relay 20 will not respond by means of supply wires 32 and 33 for the purpose which I will now describe.

It is well known in the art that resistance or reactance should be included in the circuits by which energy is supplied to the track circuits in order that the current flowing into the track when short circuited may be limited to a proper value. In the circuits here described there is a further requirement that the flow of energy by double transformation from one transmission circuit to the other shall be limited toa value which will not permit the latter circuit to deliver it at another location in sutlicient quantity to perform the function of the first circuit.

It is intended that the inherent resistance or reactance of the transformers illustrated shall be sufficient to accomplish these purposes; but should transformers of lower rerails which are separated by insulating omts 37. In this connection I provide means here shown in the form'of trans-- formers 38 and 39' for supplying current from the wires 32 and 33 and from the wires and 31 respectively to the block 34. It is to be understood however that instead of using transformers I may use any other source for the desired current. The current from the transformer 39 is supplied to the block 34 through a relay contact finger 40. The contact in the relay 40 is controlled by a coil 41 in a wire 42 bridging the block immediately in front of the block 34 so that should the current in said block in front-of the block 34 fail, the contact in the relay 40 would be broken and the current of the frequency supplied from the wires 30 and 31 would no longer be supplied to the block 34. From transformer 38 current is conveyed to the. block 34 by means of a wire 43. In a similar way theblock 35 is supplied with current of the two different frequencies by transformers 44 and 45, the latter conveying current through a relay 46. In the same way current is supplied to the block 36 through transformers 47 and 48 and a relay 49. For the block in the rear of the block 36 there are provided in the same way transformers 50 and 51 and a relay 52. This arrangement is such that current is at all times supplied to the different blocks over the wires 32 and 33. It therefore follows, as pointed out above, that when a block in advance of the block which a train is approaching is clear, the passage of the current through the particular relay will maintain the derivation of the current from the wires 30 and 31 t0 the block which the train is approaching thus showing through the various signal devices already described when the train reaches the blocks which it has been approaching that the train mayenter the block in question. Should, however, another train be in the block which the first train, is approaching, the wheels of the other train would short circuit the current in the block, thus breaking the contact in the relay in advance of the first train and discontinuing the supply of current derived from the wires 30 and 31.1;0 the block in which this train is located.-

jll will be understood, however, that when the current ceases to flow from the wires 30 and 31 in this manner in the block in which atrain is located, because of the presence of a train in the block immediately in front of the first mentioned train, nevertheless the second block in the rear of the first mentioned train would still be energized by currents of both frequencies. Therefore when a train enters the block immediately in the rear of a block that is occupied by another 'train, current derived from the wires 30 and 31 will cease to flow through the axles of the first mentioned train, thus causing the light 24 to go out, and operating the valve 1 so as to permit the brake system to apply the brakes.

The passage of current derived from wires 32 and 33 will not affect the apparatus on the train because it is of a frequency to which the latter will not respond. However, it can be seen that any number of selective relays '20 might be employed in this circuit, each responsive to a certain given frequency to thereby control various functions upon the vehicle.

In the arrangement of the system indicated in Figure 3 the parts are constructed in exactly the same manner as shown in Figure 2 except that in this instance I have shown a system in one block 53 in which it is desired to limit the speed of the train irrespective of the presence of a train in the block in advance thereof. In the case of this block no provision is made for supplying any current thereto from wires 30 and 31, but instead there is supplied thereto merely current from wires 32 and 33 through a transformer 54 connected by a relay contact finger 55 to the rails in that block and adapted to be controlled in the usual Way by a coil- 56 connected by wire 57 to the block 58 in advance of the block 53. When arranged in this manner the system will operate in such a way that when a train reaches the block 53 the light 24 will be extinguished and the automatic stopping devices operated.

* By this arrangement, furthermore, in order for a train located in the block 59 in the rear of the block 53 to proceed,'it is necessary for both of the blocks 53 and 58 in advance thereof to be clear as the current over wires 30 and 31 will notbe supplied to the block 59 except in the case where the relay containing contact finger 55 supplying current to the block 53 and the relay 60 supplying current to the block 59 have their respective coils energized from the blocks 58and 53.

Another arrangement for energizing the system may be provided instead, if desired, as shown in Figure 4. In. the arrangement as shown in this figure only current from wires 30 and 31 is supplied to blocks 61, 62, 63 and 64 by transformers 65,66 and 67 which are arranged to supply current continuously through resistances 68, 69 and 70 to the said blocks. Shunted around the resistances 68, 69, and 70, however, I have provided relays 71, 72 and 73, which when maintained with their contacts closed by coils 74, 75 and 76 supply current of sufficient strength to actuate the indicating and controlling devices on the train. When, however, the circuits through the relay contacts are broken, the current which is con tinuously supplied to the blocks through he resistances 68, (39 and 7 0 is not sufiiciently strong to actuate the controlling devices on the train'but is sufiiciently strong to energize the magnets 74, 75 and 76, so as to operate the relays 71, 72 and 73. In this way one source of current serves to perform all of the required operations.

While I have described my invention above in detail, I wish it to be understood that many changes may be made therein without departing from the spirit of my invention.

I claim:

1. A railway signaling system comprising track rails; means for supplying to said track rails, at intervals, an alternating signaling current; a vehicle for travel along said track rails; a circuit carried by said vehicle and arranged to collect energy from the signaling current on the track rails; means also carried by the vehicle for amplifying the variations in energy collected in said circuit; and vehicle governing means also on the vehicle and operated by reason of said amplified energy variations.

2. A railway signaling systemcomprising track rails, means for impressing alternating current thereon, a vehicle, a circuit on the vehicle receiving energy from the track rails, means for amplifying the variations in energy in said circuit, and vehicle governing apparatus controlled through the amplified current.

3. A railway signaling system compris ing a trackway; means for dividing the trackway into signaling sections; a source of current connectedv with each signaling sec tion and a relay device also connected with each signaling section so as to form a closed track circuit; a source of signaling current for each signaling section and connected therewith through the relay device of a section in advance; a vehicle for travel along the'trackway; a circuit on the vehicle arranged to receive energy from the signaling current in the track rails of a signaling section; an amplifier on the vehicle and included in said circuit for amplifying the variations of energy in said circuit; vehicle gov erning means on said vehicle; an electrically operated device for controlling said means, said device acting when energized to cause one operation of said governing means and when de-energizcd to cause another operation of said means; a. circuit for said electrically operated device including a source of current and said circuit being controlled as to the flow of current therein by the operation of the amplifier 'by said alternating signaling current.

4. A railway signaling system comprising track rails; means for supplying thereto an alternating signaling current; a railway vehicle, a circuit thereonarranged to receive energy from the alternating signaling current in the track rails; an amplifier'on the vehicle and included in said circuit for ainplifying the variations of energy in said cir cuit; vehicle governing means on said vehicle; an electrically operated device for controlling said means, said device acting when energized to cause one operation of said governing means and when deenergized to cause another operation of said means; a circuit for said electrically operated de vice including a source of current and said circuit being controlled as to the flow of current therein by the operation of the amplifier by said alternating signaling current. 5. Railway traflic controlling apparatus comprising track rails divided into sections; a track circuit for each section comprising a source of trackcircuit current and a track relay; means for each section for supplying alternating signaling current thereto difi'ering'in frequency from the track circuit current, said means being controlled by the track relay for the section next in advance; a vehicle; a circuit thereon in which'current is caused to flow by virtue of current in the track rails; an amplifier on the vehicle receiving current from said vehicle circuit; vehicle governingmeans; electrical means controlling said vehicle governing means and responsive to current of the frequency of said alternating signaling current but not to the track circuit current; a source of current on the vehicle; and a circuit including said electrical means and said source and controlled by said amplifier as to the flow of current.

6. Railway trafiic controlling apparatus comprising track rails; means for supplying alternating signaling current thereto; a railway vehicle; a circuit thereon arranged to. receive energy from the signaling current in the track rails; an amplifier controlled by current in said circuit for amplifying the variations of the energy in said circuit; an electroresponsive device on the vehicle, a circuit for said electroresponsive device including a source of current and the flow of current in which circuit is governed by said amplifier; and vehicle governing means controlled by said electroresponsive device.

7. Railway traffic controlling apparatus comprising track rails; means for supplying alternating signaling current thereto; a railway vehicle; vehicle governing apparatus thereon; a circuit on the vehicle receiving energy from said track rails; an amplifier controlled by the current received in said circuit; and a second circuit on the vehicle for controllingthe operationof said vehicle fit) governing means, said second circuit including a source of current and the flow of, current in said circuit Il ieing controlled by the action of said amplifier.

8. A railway signaling systcm' comprising track rails; means for supplying to said track rails at intervals an alternating signaling current; a vehicle for travel along said track rails; a circuit carried by said vehicle and arranged to collect energy from the signaling current on the track rails; an amplifie' also carried by the vehicle including a source of current for amplifying the variations in energy collected in said circuit; and vehicle governing means also on the vehicle and operated by reason of said amplified energy variations.

9. Railway traffic controlling apparatus comprising a track divided into blocks, a source of current connected across the rails of each block at the exit end thereof, means connected with the rails of each block at the entrance end thereof for modifying the character of the current supplied to the ad jacent block when the block to which said means is connected is unoccupied, a vehicle, and trafiic governing means thereon controlled by current in the track rails in advance of the vehicle and responsive to said modified current but not to the track current supplied to the block in the rear of an occupied block.

10. Railway traffic controlling apparatus comprising a plurality of successive blocks, a track circuit for each block comprising a source of track circuit current and a track relay, means for each block controlled by the track relay for the block next in advance for supplying vehicle governing current differing in character from the track circuit current to the rails of the block when said relay is energized but not when said relay is tie-energized, a vehicle, and vehicle governing means thereon receiving energy from the track rails and responsive to said vehicle governing current but not to said track circuit current.

11. In combination, a railway vehicle, a circuit thereon, means for supplying alternating current to the rails of the trackway from which an alternating signaling current is produced in said circuit. a second circuit on said vehicleincluding a. lOcal source. of current. an amplifier on the vehicle for varying the current in said second circuit in accordance with the alternations of the current collected in said first circuit, and vchicle governing means controlled by the current variations in said second circuit.

12. In combination, a, railway vehicle. a circuit thereon. means for supplying alternating current to the rails of the trackway from which an alternating signaling current is produced in said circuit, a second circuit on said vehicle including a local source of current, an amplifier in said second circuit and controlled by the first circuit for causing variations of the current in the second circuit corresponding to the alternations of the current in the first circuit but of greater amplitude, and vehicle governing means controlled by the current variations in said second circuit.

13. In combination, a railway vehicle,a circuit thereon, means for supplying alternating current to the rails of the tracltway from which an alternating signaling current is produced in said circuit, a second circuit on said vehicle including a local source of current, an amplifier on the vehicle for causing variations of the energy in the second circuit corresponding in character to the energy variations in the first circuit, and vehicle governing means controlled by the energy variations in said sec ond circuit.

14. In. combination, a railway vehicle, a circuit thereon, means for supplying alternating current to the rails of the trackway from which an alternating signaling currentis produced in said circuit, a second circuit on said vehicle including a local source of current, an amplifier on the vehicle for modifying the effect of said local source in accordance with variations of the energy in the first circuit, and vehicle governing means controlled by the modified current in the second circuit.

15. A railway traffic governing system comprising track rails, means for supplying alternating signaling current thereto, a vehicle, a circuit on said vehicle receiving energy from said rails, a second circuit on the vehicle including a local source of current, an amplifier on the vehicle for varying the current in said second circuit in accordance with the alternations of the current collected in said first circuit, and vehicle governing means controlled by the current variations in said second circuit.

16. Railway traffic apparatus comprising a trackway divided into sections; a source of alternating current for supplying current across the track rails of the section at one end thereof; a vehicle; a signaling circuit formed by the opposite track rails of each section and the wheels and axles of the vehicle as it travels along the section; a circuit on the vehicle which receives energy from the current flowing in the said signaling circuit; a second circuit on the vehicle including a source of current; an amplifier on the vehicle for varying the. current in said second circuit in accordance with the energy variations of the current collected in the first circuit; a relay device having a movable element with a gravity bias and operated by continuously maintained current variations in said second circuit; and veenergy variations in having comprising hicle governin means controlled by said relay to give sa ety indications to the vehicle.

17 Railway traffic controlling apparatus a trackway divided into sections; means for each section for continuously supplying alternating current to the rails of the section; means for controlling the supply of alternating current to the rails of the section; a vehicle; a circuit on said vehicle receiving energy from the alternating current in said track rails; a second circuit on the vehicle including a source of current; an amplifier on the vehicle responsive to energy variations in the first circuit for varyin the strength of the current in said secon circuit in accordance with the the first circuit; and vehicle governing means, operated by the continuously maintained current variations in said second circuit to give safety indications to the vehicle.

18. Railway trafiic controlling apparatus comprising a trackway divided into sections; means for each section for continuously supplying alternating current to the rails of the section; means for controlling the supply of alternating current to the rails of the section; a vehicle; a circuit on said vehicle receiving energ from the alternating current in said tracc rails; a second circuit on the vehicle including a source of current; an amplifier on the vehicle responsive to energy variations in the first circuit for varying the strength of the current in said second circuit in accordance with the energy variations in the first circuit; a relay device a movable element with a gravity bias and operated by the current in said second circuit; and vehicle governing means controlled by said relay for giving safety indications to the vehicle.

19. Railway trafiic controlling apparatus comprising a trackway divided into a plurality of sections; means for each section controlled by traffic conditions in advance for supplying alternating trafiic controlling current to the rails of the section, a vehicle, a circuit on said vehicle receiving ener y from said track rails; an am lifier on tie vehicle for amplifyin the variations in energy collected in said circuit, a relay controlled by the amplified energy variations; and vehicle governin means 'controlled by said relay.

20. In combination, a vehicle; a track therefor divided into sections; means normally supplying alternating'signaling current to the track rails of each section, said means being responsive, to the shunting action of a train in advance of the section to cut off said signaling current, said signaling current also being cut off in the rear of the vehicle due to the shunting action of its wheels and axles; a receiving circuit on the vehicle influenced by said signaling current; a localcircuit and as ource of currenton the vehicle; anamplifier on the vehicle for causing variations in the strength. of the current in the local circuit in accordance with the variations in the current in the receiving circuit produced by said signaling current; and automatic train controlling means on the vehicle acting under the influence of the variations in thestrength of the' current in' the local circuit to give a safety indication.

.21. A railway trafiic-c ontrolling system comprising a controlling rail circuit including the opposite track rails and wheels and axles of a railway train or vehicle, means for producing a flow of controlling current through said rail circuit, means on said train or vehicle for deriving electro-motive-force from said flow of current in the controlling rail circuit, micro-responsive electrical amplifying means carried on said train or vehicle and controlled by the said derived electromotive-force, and electrically controllable retar-ding apparatus carried on the train or vehicle and arranged to retard itsprogress and to be maintained in non-retarding condition by the amplified energy from said amplifying means under control of the said electro-motive-force derived from the controlling rail circuit.

22. A railway trafiic-controlling system comprising a controlling rail circuit including the opposite track rails and wheels and axles of a railway train or vehicle,.' means for'producing a flow of controlling current through said rail circuit, means on said train or vehicle for deriving electro-motive-- force from said flow of current in the'controlling rail circuit, micro-responsive electrical amplifying means carried on said train or vehicle and controlled by the said derived clectro-motive-force, and retarding apparatus carried onthe train or vehicle and arranged to retard its progress and including a governing member arranged to move in response to the amplified energy of said amplifying means from a position effecting the retarding condition of said apparatus to a position etl'ecting its non-retarding condition.

' 23. A railway signaling system comprising a controlling rail circuit including the opposite track rails and wheels and axles of a railway train or vehicle, means for producing a flow of signal-controlling current through said rail circuit, means on said train or vehicle for deriving electro-motive-force from said flow of signal-controlling current in the rail circuit, micro-variant electrical amplifying means carried on said train or vehicle and controlled by the saidderived trollable signaling means carried on the train o'rvehicle and arranged to be controlled by energy from the said amplifying means under control of the said electro-inotive-force derived from the controlling rail circuit.

24. A railway signaling system comprising a signal-controlling rail circuit includ" ing the opposite track-rails and wheels and axles of a railway train or vehicle, means for produc'inga flow of signal-controlling current in said rail circuit,'mean's on said t am or vehicle for deriving electro-motive-force from said flow of current in the signal-controlling rail circuit, micro-responsive electrical amplifying means carried on said train or vehicle and controlled by the said derived electro-motive-force, and signaling apparatus carried on the train or vehicle and including a local governing circuit and a movable member in control thereof arranged to move in response to the amplified energy of said amplifying means from a position effecting the warning indication of said apparatus to a position cfi'ec'ting its clear indication.

25. A train control system comprising a railway track and a vehicle for travel thereon, a generator furnishing alternating current of a predetermined frequency to the rails of said track, means for supplying an alternating electromotive force to the vehicle from the flow of current in the track and of the same frequency as the latter, traffic governing means on the vehicle, and means controlled by said electromotive force and responsive to said predetermined frequency but not to another frequency for controlling said trafiic governing means.

26. Railway trafiic controlling apparatus comprising track rails; a vehicle for travel thereon a circuit on the vehicle; means located in the trackway from which an alternating electromotive force of a predetermined frcquency is produced in said circuit; a second circuit on said vehicle including a local source of current; an amplifier controlled by ihe variations of electromotive force in the first circuit for causing variations, having said predetermined frequency, in the flow of current from said local source in said second circuit; vehicle governing means on the vehicle; and means on said vehicle controlled by the variations of current fiow in said second circuit and responsive to variations of said predetermined frequency but not to variations of another fre- (funcy for controlling said vehicle governing means.

27. Railway tratlic controlling apparatus comprising a vehicle, a track on which it travels, means for supplying alternating current to said track, and vehicle governing means on said vehicle controlled by said current in the track and comprising a plurality of concatenated amplifying devices.

28. Railway trafiic controlling apparatus comprising a trackway and a vehicle for travel thereon, a circuit on the vehicle, means located in the trackway from which an alternating electromotive force is produced in said circuit, a second circuit on said vehicle including a source of current, an amplifying device controlled by the alternating electromotive force in said first circuit for varying the strength of the current in said second circuit, a third circuit on said vehicle, including a source of current, a second amplifying device controlled by the variations in current strength in said second circuit for varying the strength of the current in the third circuit, the variations of current stren th in the third circuit being of greater amplitude than those in the second circuit, and vehicle governing means controlled by the variations in current strength in said third circuit.

29. Railway trafiic controlling apparatus comprising a trackway divided into block sections, a vehicle'for travel on said trackway, a circuit on said vehicle, means in the trackway from which ail-alternating electromotive force is produced in said circuit, a second circuit on said vehicle including a local source of current, an amplifier in said second circuit controlled by said first circuit and causing variations in the flow of current in the second circuit of a frequency corresponding to the alternations of electromotivc force in the first circuit, but of greater energy than could be derived directly therefrom, and vehicle governing means controlled by said second circuit.

30. Railway trafiic controlling apparatus comprising a trackway and a vehicle for travel thereon, a circuit on said vehicle, means in the trackway from which an alternating elcctromotive force is produced in said circuit, a second circuit on said vehicle including a source of current, amplifying means controlled by the alternating electromotive force in said first circuit for causing variations in the flow of current in the second circuit, and vehicle governing means controlled by the variations in the current in said second circuit.

31. Railway traflic controlling apparatus comprising a trackway divided into block sections and a vehicle for travel thereon, a circuit on said vehicle, means associated with each section and controlled by trafiic conditions in advance from which an alternating electromotive force is produced in said vehicle-carried circuit, a second circuit on said vehicle including a local source of current, amplifying means controlled by the alternating electromotive force in said first circuit for causing variations in the current in said second circuit, and vehicle governing means ccntrolled by the current variations in the second circuit.

carried circuit, a second circuit on said vehicle includng a local source of current, amplifying means controlled by the alternating electromotive force induced in said first circuit for causing variations in the current in said second circuit, and vehicle governing means controlled by the current variations in said second circuit.

33. Railway traific controlling apparatus comprising a trackway divided into block sections, a vehicle for travel on said trackway, means located in the trackway from which an alternating magnetic field is pr0-- duced on the vehicle, a circuit on the vehicle subject to said alternating-magnetic field, a second circuit on said vehicle including a local source of current, an amplifier in said second circuit controlled by the first circuit in response to the variations of said mag netic field, and producing in said second circuit alternating current corresponding in frequency to said magnetic field but of greater amplitude than could be derived directly therefrom, and vehicle governing means controlled by the current in said second circuit.

34. Railway traflic controlling apparatus comprising a trackway, a Vehicle for travel thereon, a circuit on the vehicle, means located in the trackway from which an alternating electromotive force is produced in said circuit, a second circuit on said vehicle including a source of direct current, amplif ing means on the vehicle controlled by tie alternating electromotive force in the first circuit for causing variations in the strength of current in the second circuit; a relay hav- 1: g a winding included in said second'circuit and responsive to variations of current strength in said circuit but not to direct current, and vehicle governing means controlled by said relay.

35. Railway trafiic controlling apparatus comprising a trackway, a vehicle for travel thereon, a circuit on the vehicle, means 10+ cated in the trackway from which an alternating electromotive force is produced in said circuit, a second circuit on said vehicle including a source of direct current, amplifying means on the vehicle controlled by the alternating electrmotive force in the first circuit for causing variations inthe strength of current in the second circuit; a relay having a winding included in said circuit and responsive to variations of current strength but not to direct current and said relay being so designed that its responsiveness to current variations is not impaired by the direct current in said second circuit, and vehicle governing means controlled by said relay.

36. Railway trafiic controlling apparatus comprising a trackway, a vehicle for travel thereon, a circuit on the vehicle, means located in the trackway from which an alternating electromotive force is produced in said circuit, a second circuit on said vehicle including a source ofdircct current, amplifying means on the vehicle controlled by the alternating electromotive force in the first circuit for causing variations in the strength of current in the second circuit; an induction motor relay having a winding included in said second circuit, and vehicle governing means controlled by said relay.

37. Railway trafiic controlling apparatus comprising a trackway, a vehicle for travel thereon, a circuit on the vehicle, means located in the trackway from which an alternating electromotive force is produced in said circuit, a second circuit on said vehicle including a source'ofdirect current, amplifying means on the vehicle controlled by the alternating electromotive force in the first circuit for causing variations in the strength of current in the second circuit; an induction motor relay having a winding supplied with energy by said second circuit, and vehicle governing means controlled by said relay.

38. Railway trafiic controlling apparatus comprising a trackway, a vehicle for travel thereon, a circuit on the vehicle, means lo- .cated in the trackway from which an alternating electromotive force is produced in said circuit, a second circuit on said vehicle including a source of direct current, amplifying means on the vehicle controlled by the alternating electromotive force in the first circuit for causing variations in the strength of current in the secondcircuit; a relay having a winding included in said second circuit, a rotor of non-magnetizable material and a contact actuated by said rotor; and vehicle governing means controlled by said relay contact.

' 39. Railway tratiic controlling apparatus comprising a trackway, a vehicle for travel thereon, a circuit on the vehicle, means located in the trackway from which an alternating electromotive force is produced in said circuit, a second circuit on said vehicle including a source of direct current, amplifying means on the vehicle controlled by the alternating electromotive force in the first'circuit for causingvariations in' the strength of current in the second circuit; a'relay comprising an iron core having an air gap, a' winding on said core and included in said second circuit, a rotor of non-magnetizable material moving in said air gap and a contact actuated by said rotor; and vehicle governing means controlled by said relay contact.

40. Railway trafiic controlling apparatus comprising a trackway, a vehicle for travel thereon, a circuit on the vehicle, means located in the-trackway from which an alternating electromotive force 'is produced v.in said circuit, a second circuit on said vehicle including a source of directfeurrent, ampli ing means on the vehicle controlled by t e alternating electromotive force in the first circuit' for causing variations in the strength of current in the secondcircuit; arelay having a winding included in said second circuit and responsive to current variations of the freggency of the alternating electromotivefo'rce created in said first circuit but not to variations of a different frequency, andvehicle governing means controlled by said rela 41. Railway tratli c controlling apparatus comprising a trackway, a vehicle for travel thereon, a circuit on the vehicle, means located in the trackway from which 'an alter nating electromotive force is produced in said circuit, a second circuit on said vehicle including a source of direct current, amplifying means on the vehiclev controlled by the alternatingelectiomotive force in the first circuit for causing variations in the strength of current in the second circuit; a regenerative circuit for said amplifying means re ceiving eleetromotive force from said second circuit, and vehicle governing means controlled by the current variations in said.-

second circuit.

42. Railway trafiic controlling apparatus comprising a trackway and a vehicle for travel thereon, a receiving circuit on the vehicle, means in the trackway from which an alternatin electromotive force is produced in sai circuit, a second circuit on said vehicle'including a source of direct current; a microphone amplifier comprising a magnet receivlng energy from said receiving circuit, an armature controlled by said magnet, and a carbon mass included in said second circuit and the resistance of which mass isvaried by the motion of said arma-- ture; and vehicle governing means controlled by the current variations in said second circuit.

43. Railway traflic controlling apparatus comprising a trackway and a vehicle for travel thereon, a receiving circuit on the vehicle, means in the tra'ckway from which an alternating electromotive force is produced in said circuit, a second circuit on said vehicle including a source of direct current; a microphone amplifier comprising a magnet receiving energy from said receiv-' ing circuit, an armature controlled by said magnet, and a carbon mass included in said' second circuit and the resistance of which mass is varied by the motion of saidarmature; regenerative means for said amplifier comprising a second magnet acting on said armature and connected in the second circuit in multiple with the carbon mass, and vehicle governing means cont-rolled by the current variations in said second circuit.

44. The method of controlling trafiic, which consists in producing an alternating disturbance along a trackway carrying traffic to be controlled, governing said disturbance by trafiic conditions in advance, producing by said disturbance an alternating E. M. F. in a vehicle to be controlled, influencing thereby a local source of energy -to produce energy changes greater than could be directly derived from the disturbance, and causing said local energy changes to actuate traffic controlling means.

45. The method of controlling traffic, which consists in producing, along a trackway carrying trafiic to be controlled, an alternating disturbance having a predetermined frequency, governing said disturbance by trafiic conditions in advance, producing by said disturbance an alternating E. M. F. in a vehicle to be controlled, causing said E. M. F. to control a source of direct current on said vehicle to produce al.- ternating currents of the same frequency but greater energy than that directly derived from said disturbance, and actuating traffic controlling means thereby.

46. The method of controlling trafiic, which consists in producing along a trackway carrying trafiic to be controlled, an alternating disturbance having a predetermined frequency, governing said disturbance by traffic conditions in advance, producing by said disturbance an alternating E. M. F. in a vehicle to be controlled, controlling thereby a local source of direct current-to produce alternating current of the same frequency, regeneratively amplifying said current, actuating a signal on said vehicle in accordance with changes in said E. M. F and actuating traflic controlling means on said vehicle by said amplified current to permit manual control of said train only when said manual control is in accord with said signals.

47. In a railway block signal system, in combination, a section of tratlic rails constituting a block, a source of current for energizing said section, a coil across said rails, a switch under the influence of said coil, and an alternating current circuit passing through said switch to a preceding block.

48. In a railway block signal system, a track divided electrically into signal sections, a plurality of current sources of different fr uencies, means associated with and control ed by each of said sections for connecting said current sources to preceding sections.

4.9. The method of controlling railway traflic which consists in producing in the track rails a periodic current of commercial frequency, deriving from said rail current a periodic E. M. F. available on a, railway rophone' amplifier on vehicle, employing .said derived E. to

e- 1 maniame on th f el i l "and employing the output ener' of said liieans to govern trill c-eiintr'ol ling'meaiis on the vehicle. I l f 59f Railway trafiic-controlling ap aratus l for producing a periotlic ciir' ent in the'traek'rails, cans for deriving E1 E; therefrom" on a moving vehicle, polarized electromagnetic telephonic micsaid vehicle arranged to be controlled by said derived E. and shimmers-11mgapparatus on the vehicle governed by the output energy of said microphonel railway traiiic-controlling system coniprisin'g means 'tor'pro'ducing a flow of periodic current" the track rails, means on comprising means III a railway'Wehicle for "deriving from said rail" current' a periodic E. F., a cascade seriesof amplifiers on thev'ehicle arranged to'be excited'by'said'de'rived EJM; F., and traifie "controlling means on the vehicle governed'loy the output circuit of said cascade amplifier series; z

' 52, At rail'way trafiic-controlling system comprising means for producing a n w of periodie eurrent' in thet'rack railsfm'eans on a railway vehicle rail current a periodic a regenerati've amplifier on the vehicle havin'g'its input circuit excited by'said derived E. MFR, and

trafiic-controlling means on'the' vehicle governed by the output circuit'of said amplifier.

53. A railway trafiic-eontrolling system comprising means for producing a fiow'of periodic current in the track rails, means on a railway vehicle for deriving from sa d rail current a periodic E. M. F., a telephonic waveform-repeating amplifier on the vehicle receiving said derived E. F. in its input circuit and reproducing the waves thereof, in its output circuit, and traffic-controlling means on the vehicle responsive to and governed by said repeated waves delivered by the amplifier.

' 54. A track circuit; a vehicle circuit deriving energy from the track circuit; a second vehicle circuit deriving energyfrom a local source; a controlling element whereby the current in the second vehicle circuit is varied in accordance with the current in the first vehicle circuit; and a train control device governed by the current in the second vehicle circuit.

55. A railway traffic controlling system comprising a controlling rail circuit includin the opposite track rails and wheels and ax es of a railway train or vehicle, means for producing a flow of controlling current through said rail circuit, means on said train or vehicle for deriving electromotive force from said flow of current in the controlling rail circuit, micro-responsive electrical amplifying means carried on said train or veel ctromotive force;

for deriving from said hicle and controlled the said derived electromotive tom-1e, and electrically com otlebl ee ine apt-a w e t train or vehicle and arranged'to' retard its pregress and to teases-neat" the amplified ner y f d ninth "ht: vifiail'l d control at the sa'id eleet motivator-deaci-i'vedfrom the cane-felling em, circuit-f l i 5e; railway name fcoiiti'ollin'g system comprising teams-a r ma circuit includtl'ie opposite l rails and Whel and axles of a' 'railivaftrain or vehiele, means for producing a flow of controlling current through said rail "circuitf team's on said train" or vehicle" for deriving" electromotive force from "said h v of currentin' th'e'm'mtrolling 'r'ail circuit, micro-responsive electric'al amplifying means carried on said train or vehicle and controlled the said derived nd retarding apparatus c iedonthe train'orvehicle arranged to retard its progress and including a local governing circuit andamo'vab'le member in eons-o1 thereof arranged to move inresponse to" the amplified energy of "said amplifying means from a position effecting the retardiii g eOn-d1t1on=-" f said apparatus' to a position effecting its non-retarding condition.

' 57; A railway signaling system comprismg a "controlling rail circuit including. the oppositetrack'railshnd wheels and axles of a'r'ailway train or vehicle, means for producing' a flow of controlling current through said'rail circuit, means on saidtrain or vehicle for deriving electromotive force from said flow of current in the controlling rail circuit, micro-res onsive electric amplifymg means carrie on said train or vehicle and controlled by the said derived electromotive force, and visual signaling means carried by the train or vehicle and arranged 'to be energized by the amplified energy from said amplifying means to eiiect its clear indieati'on'. 58. A railway signaling system comprising a controlling rail circuit including the opposite track rails and the wheels and axles of a railwa train or vehicle, means for producing'a ow of controlling current through said rail circuit, means on said train or vehicle for deriving electromotive force from said current flow in the controlling rail circuit,'miero-variant electric amplifying means on said train or vehicle controlled by said derived electromotive force, and signalling apparatus carried by the train or vehicle and including a governing member arranged to move in response to the amplified energy of said amplifying means from a position effecting the warning indication of the apparatus toa position efiecting its clear indication.

59. In a railway signal system, in combination, a circuit for carrying alternating current of a definite frequency, means in said circuit for normally maintaining it in one condition, and another circuit under the influence of a train for afi'ecting said means.

60. In a railway signal system, in combination, a circuit for-carrying alternating current of a definite frequency, an indicating device responsive to said current, an electrO- magnetic switch in said circuit, and another circuit connected to said switch and having a connection across the traflic tracks in advance of said indicating device, whereby the axle of a train preceding said indicating device will effect it.

61..A trafiic regulating system comprising a track rail, means for impressing a varying current thereon, a vehicle, a circuit on the vehicle receiving energy from the track rail, an amplifier controlling a greater flow of energy in accordance with the variations of the received energy, and trafiic regulating apparatus controlled by the increased energy.

62. A traflic regulating system comprising a vehicle, a circuit thereon deriving a relatively small power from'a rail circuit, a second circuit for regulating the progress of the vehicle and a static amplifier interposed between the first and second train circuit.

' '63. A trafiic regulatingsystem comprising a vehicle, a circuit thereon'deriving power from a rail circuit, a second circuit including a source of power, and a traflic regulating device and a variable resistance influenced by the first train circuit.

64. A traffic regulating system comprising a rail circuit, a train carried circuit coupled therewith, a variable resistance amplifying device controlled by the second circuit, and a third circuit including the variable resistance and an independent source of electroniotive force.

65. In a traflic regulating system a track circuit, a roadside relay responsive to cur-.

rent in the track circuit, and a train borne amplifier and relay selectively responsive to track current of one character and unresponsive to track current of another character.

66. In a traffic regulating system, a train borne circuit picking up indications of relatively little power, and a second circuit having its own source of power coupled to the first circuit by an element which controls the intensity of power in the second circuit but does not originate the flow of power.

In testimony whereof, I have signed my name to this specification.

ELI J. BLAKE. 

